Fix address-instability in MultiSegmentArena by storing *Segment and validating via (id, arena storage)#607
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lthibault merged 1 commit intocapnproto:mainfrom Oct 24, 2025
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LGTM. Approving once it clears CI.
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Do I need to cut a release? |
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Yes, I think so. This is due to previous version is buggy with MultiSegment. |
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This attempts to fix #606 -
MultiSegmentArena:preferred segment is not part of the arena[]Segmentwith[]*Segmentin MultiSegmentArena to avoid address-instability on append.Segment(id)return the stable pointer frommsa.segs(no&msa.segs[id]).Allocate, validate the preferred segment in O(1) by checkingseg.idis in-range andmsa.segs[seg.id] == seg; remove the linear pointer scan.msa.segslength in sync with the byte-storage (msa.segs[i].data).Release()zeroises and returns buffers, then clears pointers safely.